1. Field of the Invention
The invention relates to a method for repairing or replacing a connecting device for electrical connection and for supplying and carrying away the coolant to and from the hollow conductor elements of the stator winding bars of electrical machines, in the case of which connecting device the hollow conductor elements and, if appropriate in the case of a stator winding which also comprises solid conductor elements as well as hollow conductor elements, all the conductor elements are surrounded by a metallic component and are brazed thereto and to one another, which component overhangs the conductor elements forming a water chamber and ends in a connecting fitting for coolant supply and carrying the coolant away.
2. Discussion of Background
In the stator winding overhang of water-cooled electrical machines, the coolant is supplied from annular header lines via insulating hoses to the so-called water chambers at the end of the conductor bars. The water chamber is formed by a connecting device in which the hollow conductor elements are surrounded by a metallic component and are brazed or soldered thereto and to one another. The metallic component overhangs the conductor elements to form this water chamber. It ends in a connecting fitting for coolant supply and carrying coolant away. The connecting device is at the same time also used as the electrical connection.
The connecting device is subject to high mechanical loads (vibration) during operation. Even very small leakages lead to consequential damage to the electrical machine. If such damage occurs, the brazed or soldered joints--if at all possible--must be replaced. In general, only the removal or even the complete replacement of the stator winding remains. There is thus a major requirement for a repair method which can be carried out without removal of the stator winding.